code: def add_args(parser):
      rnn.RNNModel.add_args(parser)
      char_encoder.add_args(parser)
  
imports: import logging
  from ast import literal_eval
  import torch
  import torch.nn.functional
  from fairseq.models import FairseqEncoder, register_model, register_model_architecture
  from pytorch_translate import char_encoder, model_constants, rnn, utils, vocab_constants
  from pytorch_translate.common_layers import Embedding, VariableTracker
  from pytorch_translate.data.dictionary import TAGS
label_desc: Use image node_id 2 for calling the CharSourceModel obj's underlying member method code with example usage: obj.add_args(parser) without return types